Would be great if EXI could be used with mobile devices: "EXI can be used in XMPP streams to efficiently compress data transmitted between the server and the client" http://xmpp.org/extensions/xep-0322.html
Feature requests for clients:
Feature requests for other servers:
As far as I am aware, there are no readily available and suitably libraries we could use. I have only heard of a single proprietary library. Without that or directed funding I don't see this being implemented.